I would say that the higher you get up the privilege level tree, the worse the software becomes. The people writing legacy BIOS extensions are the absolute bottom of the barrel.
In modern software development, this is usually a task for the junior engineer as it's code the client never sees. Only in specific industries where the client is also highly technical (e.g. a data-acquisition component in an instrument) where the quality of the low-level code matters, would it be someone senior. In those cases, it usually matters a lot more than the UI.